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تسجيل مستخدم جديدDomains of pulsational instability of low-frequency modes in rotating upper main-sequence stars
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We determine instability domains on the Hertzsprung-Russel diagram for rotating main sequence stars with masses 2-20 $mathrm M_odot$. The effects of the Coriolis force are treated in the framework of the traditional approximation. High-order g-modes with the harmonic degrees, $ell$, up to 4 and mixed gravity-Rossby modes with $|m|$ up to 4 are considered. Including the effects of rotation results in wider instability strips for a given $ell$ comparing to the non-rotating case and in an extension of the pulsational instability to hotter and more massive models. We present results for the fixed value of the initial rotation velocity as well as for the fixed ratio of the angular rotation frequency to its critical value. Moreover, we check how the initial hydrogen abundance, metallicity, overshooting from the convective core and the opacity data affect the pulsational instability domains. The effect of rotation on the period spacing is also discussed.
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